In a communication network, such as an Internet Protocol (IP) network, each node and subnet has limitations on the amount of data that can be effectively transported at any given time. In a wired network, this is often a function of equipment capability. For example, a gigabit Ethernet link can transport no more than 1 billion bits of traffic per second. In a wireless network the capacity is limited by the channel bandwidth, the transmission technology, and the communication protocols used. A wireless network is further constrained by the amount of spectrum allocated to a service area and the quality of the signal between the sending and receiving systems. Because these aspects can be dynamic, the capacity of a wireless system may vary over time.
Historically, communication systems have segregated traffic by classes of service (CoS) in the core, such as in a packet gateway (P-GW) in an LTE system. This has the benefit that operator provided services such as voice and video from the operator's own or coordinated content delivery network (CDN) are able to be given quality of service (QoS) guarantees such as guaranteed bit rates (GBR). Traffic not associated with operator provided services is typically less differentiated, leading to heterogeneous traffic grouped into the same CoS. Further, this traffic is often provided resources on a best effort basis, ignoring the QoS needs of the specific application generating the traffic, and ignoring the quality of experience (QoE) perceived by the end user.
Additional communication traffic may be from over-the-top (OTT) services, that is, services that are not operator provided or coordinated. Skype voice over internet protocol (VoIP), YouTube progressive download video, Netflix streaming video, and Pandora radio streaming audio are examples of OTT services. OTT voice and video services tend to be grouped together as best effort traffic along with email, social networking, and file transfer. When a network becomes congested, the OTT services are typically all treated the same regardless of the impact in perceived quality by the end user. They are typically scheduled as the same CoS. Additionally, OTT services are typically grouped into the same logical bearer. In today's communications systems, admission control is performed on a logical bearer basis without regard to the mix of services on the bearer. Consequently, real-time services such as voice, streaming video, and streaming audio are perceived to have a substantial degradation in QoE relative to non-real-time services such as email.